Overfeeding organic nutrients?

W

waktoo

Well-Known Member
Northwood said:
Perhaps not, but I think he's right on this one. There have been literally hundreds of peer reviewed research papers published in recent decades that document the negative effects of phosphorus on the uptake of many micronutrients, as well as how manures and even excessive plant biomass (including compost) contributions can cause that excess. Here's just one example (full paper): https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3355622/
Click to expand...
I was hoping for something containing experimental data, as it applies to soilless culture.

There's certainly some truth inherent in the example provided, but it lacks context. And I certainly don't see excessive amounts of P reported in the test he provided. Not if you're looking at the ppm's, anyways. I have a lot of concerns as to accuracy of the values provided when used to test soilless mixes high in SOM content. Additionally, that test combines CEC and solution data into one value, which I think makes it more difficult to use as a tool for properly diagnosing soil nutrient "issues". Says it right here at about ~23:00...

www.kisorganics.com

Episode 17: Understanding Soil Testing with Kris Borgman

Our guest this week is Kris Borgman. Kris earned a Bachelors of Science in Crop and Soil Science from Washington State University and has 19 years’ experience in agronomy, field management, sustainable programs surrounding agricultural, turf and natural environments. He is the currently the...
www.kisorganics.com www.kisorganics.com

What was inherently missing in the copy/paste example provided is the fact that P precipitation reactions with the trace elements Fe, Cu, Mn, and Zn are solution pH dependent. Those trace elements also tend to bind strongly to the soil's CEC, something having to do with ionic radius and valence. I would propose that those testing their soils and finding certain trace elements missing/insufficient in the soil solution start paying more attention to pH. High(er) pH's lock out those elements through precipitation, and the high pH keeps those bound to the CEC and unavailable for plant absorption, as the soil solution is carrying insufficient levels of H+ to push those elements held by the CEC back into the soil solution where they're plant available. The aforementioned trace elements are more soluble and plant available at pH ranges ~6, "organic" soilless mixes or otherwise. pH controls nutrient solubility in the soil solution. Looking at the following example, it's important to recognize that we don't water with fertilizer solutions, so I don't believe the wider pH ranges mentioned apply to the soil mixes that we build.




Just my 2c....
 
Last edited:
N

Northwood

Well-Known Member
waktoo said:
I have a lot of concerns as to accuracy of the values provided when used to test soilless mixes high in SOM content.
Click to expand...
Well that I can certainly agree to that. It's also why labs offer specialty tests for these types of horticultural mediums (and composts) in order to provide more relevant and accurate analysis - for more money of course. Most accrediting services are pretty transparent, and often state that a standard or basic test is only useful for mineral (field) soils right on their website.

My apologies for not reading the entire thread. I thought your post I responded to was suggesting that you can't have too much phosphorus.
 
MustangStudFarm

MustangStudFarm

Well-Known Member
Northwood said:
Perhaps not, but I think he's right on this one. There have been literally hundreds of peer reviewed research papers published in recent decades that document the negative effects of phosphorus on the uptake of many micronutrients, as well as how manures and even excessive plant biomass (including compost) contributions can cause that excess. Here's just one example (full paper): https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3355622/
Click to expand...
What, you agree with me??? I thought for sure that both of you were here to bash on me. You win, this is your forum, I don't care anymore...
 
MustangStudFarm

MustangStudFarm

Well-Known Member
waktoo said:
I was hoping for something containing experimental data, as it applies to soilless culture.

There's certainly some truth inherent in the example provided, but it lacks context. And I certainly don't see excessive amounts of P reported in the test he provided. Not if you're looking at the ppm's, anyways. I have a lot of concerns as to accuracy of the values provided when used to test soilless mixes high in SOM content. Additionally, that test combines CEC and solution data into one value, which I think makes it more difficult to use as a tool for properly diagnosing soil nutrient "issues". Says it right here at about ~23:00...

www.kisorganics.com

Episode 17: Understanding Soil Testing with Kris Borgman

Our guest this week is Kris Borgman. Kris earned a Bachelors of Science in Crop and Soil Science from Washington State University and has 19 years’ experience in agronomy, field management, sustainable programs surrounding agricultural, turf and natural environments. He is the currently the...
www.kisorganics.com www.kisorganics.com

What was inherently missing in the copy/paste example provided is the fact that P precipitation reactions with the trace elements Fe, Cu, Mn, and Zn are solution pH dependent. Those trace elements also tend to bind strongly to the soil's CEC, something having to do with ionic radius and valence. I would propose that those testing their soils and finding certain trace elements missing/insufficient in the soil solution start paying more attention to pH. High(er) pH's lock out those elements through precipitation, and the high pH keeps those bound to the CEC and unavailable for plant absorption, as the soil solution is carrying insufficient levels of H+ to push those elements held by the CEC back into the soil solution where they're plant available. The aforementioned trace elements are more soluble and plant available at pH ranges ~6, "organic" soilless mixes or otherwise. pH controls nutrient solubility in the soil solution. Looking at the following example, it's important to recognize that we don't water with fertilizer solutions, so I don't believe the wider pH ranges mentioned apply to the soil mixes that we build.




Just my 2c....
Click to expand...
I'm not spending my time arguing with you. You had your chance to impress me last year, but you blew it by being a dick...
 
VILEPLUME

VILEPLUME

Well-Known Member
So in short, it is possible to overfeed in organics?

And should you flush the last week if you overfeed to get the harshness taste out or does this not apply when doing organics?

I'm extremely tempted to go back to synthetic nutes.
 
W

waktoo

Well-Known Member
MustangStudFarm said:
I'm not spending my time arguing with you. You had your chance to impress me last year, but you blew it by being a dick...
Click to expand...
Argue? Who's arguing? I'm attempting to engage in an open discussion of ideas...

Last year? I haven't attempted to engage you in conversation in over ~2 1/2 years, for this very reason. You are incapable of dealing with cognitive dissonance.

I'll offer you another shot at showing everyone here where/when I was EVER a dick to you.

I'll wait patiently while you figure out how to use the search function...
 
myke

myke

Well-Known Member
VILEPLUME said:
So in short, it is possible to overfeed in organics?

And should you flush the last week if you overfeed to get the harshness taste out or does this not apply when doing organics?

I'm extremely tempted to go back to synthetic nutes.
Click to expand...
Dont give up lol,Im new also to this organic thing.But I did keep a couple hydro plants going.The learning curve for organic is a long one so keep at it.I made up a bunch of clones with different soil mixes to maybe speed up the curve.One thing forsure is they grow really slow lol.
 
W

waktoo

Well-Known Member
MustangStudFarm said:
I have traumatic brain injury(TBI), do you want to keep making fun of my disability?
Click to expand...
My man, I am fully aware of the issues you suffer from by way of combat related head trauma. I was not making fun of you, and am unsure as to how you may have drawn that conclusion. I am not that kind of person. And as far as me having acted like a "dick" to you in the past, I really do believe that you have me mixed up with someone else.

It's been a minute (~2 1/2 years) since we last conversed about your soil issues, at that time discussing the high bicarbonate content of your well water. You said you'd taken care of that aspect of consideration with RO filtration, so I let it go. But you still have issues with your soil...

~2 1/2 years is a long time. Since then, I've increased my understanding relevant to the chemical and physical characteristics of soilless container mixes, and how they affect nutrient availability.

I have a few ideas. Would you care to discuss them? We can do it through PM if you prefer. If not, that's fine too.
 
You must log in or register to reply here.
Top